On-Demand Power Supply Current Modification System and Method for an Integrated Circuit

ABSTRACT

A circuit that selectively connects an integrated circuit to elements external to the integrated circuits. The circuit includes an input/output element that selectively connects an input/output pin as a function of a power requirement or a signal bandwidth requirement of the integrated circuit. The input/output element includes one or more switching devices that connect the input/output pin to an external element, such as a power supply or external signal path. The input/output element also includes one or more switching devices that connect the input/output pin to an internal element, such as a power network or internal signal line.

FIELD OF THE INVENTION

The present invention generally relates to the field of integratedcircuits. In particular, the present invention is directed to anon-demand power supply current modification system and method for anintegrated circuit.

BACKGROUND

Advancements in technology and manufacturing capabilities change theoperational characteristics of a semiconductor device. While thesechanges include improvements in overall performance and processingcapabilities, they also include corresponding increases in, e.g., powerdensity requirements. Unfortunately, changes in the power density of asemiconductor device oftentimes increase faster than the structuralchanges to the device necessary to meet the increased power needs.Indeed, physical constraints to the overall device may limit thesestructural changes. In one example, although certain improvements to asemiconductor device may include an increase in power density, itsability to meet the increased power requirements is limited by itsinput/output capabilities.

SUMMARY OF THE DISCLOSURE

In one embodiment, a circuit for selectively connecting an integratedcircuit to a plurality of external paths, the plurality of externalpaths including a first signal path and an external power supply, thecircuit including a second signal path internal to the integratedcircuit; a power network internal to the integrated circuit; and aninput/output element configured to switch amongst a plurality of modesincluding a first mode and a second mode, the first mode connecting thefirst signal path to the second signal path via the input/outputelement, the second mode connecting the power network to the externalpower supply via the input/output element.

In another embodiment, a circuit for selectively connecting one or moreexternal paths with an integrated circuit, the one or more externalpaths including a first signal path, the circuit including a secondsignal path internal to the integrated circuit; a power network internalto the integrated circuit; a first means for switching amongst aplurality of inputs including the second signal path and the powernetwork; a second means in electrical communication with the firstmeans, the second means for switching amongst a plurality of externalpaths including the first signal path and the power supply, wherein whenthe first means is connected to the second signal path, the second meansis connected to the first signal path such that the second signal pathand the first signal path are in electrical communication, and when thefirst means is connected to the power network, the second means isconnected to the external power supply such that the power network andthe power supply are in electrical communication.

In still another embodiment, a method of modifying the power supplycurrent to an integrated circuit, the integrated circuit having aninput/output pin, the method including determining a power supplyrequirement from the operation of the integrated circuit; andalternately connecting the input/output pin to an external signal pathor an external power supply as a function of the power supplyrequirement.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, the drawings show aspectsof one or more embodiments of the invention. However, it should beunderstood that the present invention is not limited to the precisearrangements and instrumentalities shown in the drawings, wherein:

FIG. 1 is a schematic diagram of one embodiment of a circuit forconnecting elements internal to an integrated circuit with elementsexternal to the integrated circuit.

FIG. 2 is a schematic diagram of another embodiment of a circuit forconnecting elements internal to an integrated circuit with elementsexternal to the integrated circuit.

FIG. 3 is a schematic diagram of yet another embodiment of a circuit forconnecting elements internal to an integrated circuit with elementsexternal to the integrated circuit.

FIG. 4 is a flow diagram of an optional algorithm implemented in anembodiment of a circuit, such as the circuit illustrated in FIGS. 1, 2and 3.

DETAILED DESCRIPTION

FIG. 1 illustrates one embodiment of a system 100 for selectivelyconnecting integrated circuit 105 to elements external to the integratedcircuit. These external elements include, but are not limited to, asignal path, a power supply, a test device, and any combinationsthereof. In the present example, the external elements include anexternal signal path 110 and an external power supply 115.

Integrated circuit 105 may be an electronic circuit, or combination ofelectronic circuits, that perform functions important to electronicdesign. Examples of an integrated circuit (e.g., integrated circuit 105)include, but are not limited to, a micro-processor, a micro-controller,an application specific integrated circuit (ASIC), an applicationspecific standard product (ASSP), a customer specific standard product(CSSP), a mixed signal IP, and any combinations thereof. In the presentexample, integrated circuit 105 is an integrated circuit chip havinginternal elements that require communication to and from externalelements, such as those external elements discussed above. Examples ofan internal element include, but are not limited to, a signal path, apower network, and any combination thereof. Here, these internalcomponents include an internal signal path 120 and an internal powernetwork 125. An internal signal path (e.g., internal signal path 120)may be any path that electrically communicates one or more data elementsas is known by those of ordinary skill. A power network (e.g., powernetwork 125) distributes power to portions of integrated circuit 105.

System 100 also includes an input/output element 130. An input/outputelement 130 provides selective electrical connection between theelements internal to integrated circuit 105 and the elements external tointegrated circuit 105. In one example, input/output element 130provides this selective connection by switching between a plurality ofmodes. In one mode, input/output element 130 electrically connectsexternal signal path 110 with internal signal path 120. In another mode,input/output element 130 electrically connects power supply 115 withpower network 125.

System 100 further includes a controller 135 that communicates withinput/output element 130. Controller 135 controls the switching ofinput/output element 130, such as, for example, by switchinginput/output element 130 from one mode to another mode. In this example,controller 135 may be associated with an optional algorithm 140 thatinstructs the switching of input/output element 130. Algorithm 140 mayinclude a set of instructions that control the switching input/outputelement 130, as described in more detail below. In one example,controller 135 may be hardware based on executing logic for controllinginput/output element 130.

Examples of a controller include, but are not limited to, a processor, aflip-flop state machine with control logic, and any combination thereof.In the present example, controller 135 is positioned on or withinintegrated circuit 105. It is contemplated, however, that alternativeconfigurations of controller 135 may provide that it be located externalto integrated circuit 105. In still other configurations of system 100,controller 135 can be incorporated within input/output element 130, suchas, for example, within the circuit structure of input/output element130.

FIG. 2 illustrates another embodiment of a system 200 for selectivelyconnecting external elements (an external signal path 210 and a powernetwork 215) to internal elements (internal signal path 220 and powernetwork 225). The internal and external elements are connected to aninput/output element 230 that is controlled via a controller 235 and anoptional algorithm 240. In the present example, input/output element 230includes a switching device 245 and a switching device 250. A switchingdevice (e.g., switching devices 245, 250) may be any electronic devicethat can selectively switch between one or more inputs and/or one ormore outputs. Examples of a switching device include, but are notlimited to, a pass gate multiplexer, a relay, a switching circuit, andany combinations thereof.

Input/output element 230 also includes an electrically conductive wire255 that can be connected to the internal and external elements viaswitching device 245 and switching device 250. In one example, wire 255may be an input/output pin. The electrical connection of wire 255 can bechanged by switching device 245 and switching device 250. In one aspect,switching device 245 is configured to switch electrical connection ofwire 255 between signal path 220 and power network 225. In anotheraspect, switching device 250 is configured to switch electricalconnection of wire 255 between signal path 210 and power supply 215.

In one implementation of an on-demand system and method, the electricalconnection of wire 255 with the various internal and external elementscan vary as a function of the operating condition of integrated circuit205. A variety of operating conditions may influence the operating modeof input/output element 230. Examples of an operating condition include,but are not limited to, a high-power condition, a low-power condition, ahigh signal connectivity condition, a low signal connectivity condition,and any combinations thereof. In one example, as integrated circuit 205requires less power and/or signal throughput, input/output element 230(e.g., with instructions from controller 235) may switch to a firstoperating mode.

Input/output element 230 may selectively switch between a plurality ofoperating modes In one mode, switching device 245 electrically connectsto internal signal path 220 and switching device 250 electricallyconnects to external signal path 210, thereby electrically connectinginternal signal path 220 and external signal path 210 via wire 255. Inanother mode, switching device 245 electrically connects to powernetwork 225 and switching device 250 electrically connects to powersupply 215, thereby electrically connecting power network 225 andexternal power supply 215 via wire 255.

FIG. 3 illustrates yet another embodiment of a system 300 forselectively connecting the internal and external elements of anintegrated circuit 305. In this example, system 300 connects externalelements (an external signal path 310 and a power supply 315), withinternal elements (an internal signal path 320 and a power network 325).The connection occurs via an input/output element 330 that is connectedto a controller 335, optionally having an algorithm 340. Input/outputelement 330 includes a switching device 345 and a switching device 350that switch the connection of an input/output pin 355 with the internaland external elements.

Controller 335 includes electrical devices that allow controller 335 toswitch switching devices 345, 350. In one example, controller 335includes a control I/O 335 a and I/O arbiter 335 b. Those of ordinaryskill will be readily familiar with these devices, as well as otherdevices, designs and configurations in connection with controller 335such that they need not be described in any detail herein, other than tothe extent necessary to describe how features of the present disclosuremay be implemented. Control I/O 335 a and I/O arbiter 335 b electricallycommunicate with switching devices 345, 350, respectively. A pluralityof switching devices can be arranged in a manner so as to allowcontroller 335 (e.g., through control I/O 335 a and I/O arbiter 335 b orother electrical configuration) to control all of the switching devices.In the present example, a single input/output pin 370 is used to controlswitching device 350. In other examples, multiple pins may be utilizedto transfer one or more control signals to one or more switchingelements, such as switching element 350. Although only a single pair ofswitching devices 350,355 is illustrated, it is contemplated that otherembodiments of system 300 can include a plurality of pairs of switchingdevices that are arranged to electrically communicate in a serialrelationship, such that a single input/output pin can be used to controlthe series of switching devices.

In this embodiment, system 300 varies the connection of input/output pin355 with the internal and external elements in accordance with thefunctional requirements of integrated circuit 305. As illustrated inFIG. 3, controller 335 communicates with a logic element 337 ofintegrated circuit 305 and controls switching devices 340, 345 inresponse to power supply requirement 365. A power supply requirement(e.g., power supply requirement 365) provides information orinstructions to controller 335 about the functional requirements ofintegrated circuit 305. These functional requirements can include, forexample, a requirement for additional input/output pins to provideincreased power and/or a requirement for additional input/output pins totransmit signals between the internal and the external elements.Examples of a power supply requirement include, but are not limited to,a power requirement 365 a, a signal bandwidth requirement 365 b, and anycombination thereof.

Controller 335 responds to one or more of input requirements 365 byswitching input/output element 330. In one example, controller 335responds to power requirement 365 a by switching input/output element330 into a power mode. A power mode allows the transmission of a powersignal from the external elements, via input/output pin 355, to theinternal elements. In a power mode, controller 335 connects switchingdevice 350 with power supply 315 and connects switching device 345 withpower supply 325. In another example, controller 335 responds to signalbandwidth requirement 365 b by switching input/output element 330 into asignal mode. A signal mode allows the bidirectional transmission of adata signal, via input/output pin 355, between external elements and theinternal elements. In a signal mode, controller 335 connects switchingdevice 350 with signal path 310 and connects switching device 345 withsignal path 320.

As discussed above, controller 335 can be associated with an algorithm340 that provides instructions for determining the switching ofswitching devices 345, 350. In one example, algorithm 340 includes a setof instructions having pre-determined information describing the powerrequirements and/or the signal bandwidth requirements of integratedcircuit chip 305. In another example, algorithm 340 includes a set ofinstructions for determining power requirement 365 a and signalbandwidth requirement 365 b from input requirement 365 provided byintegrated circuit chip 205. In still another example, algorithm 340includes a set of instructions for responding to power requirement 365 aand signal bandwidth requirement 365 b received from integrated circuitchip 305.

Referring next to FIG. 4, and also FIG. 3, an example 400 of analgorithm that responds to power requirement 365 a and/or signalbandwidth requirement 365 b is illustrated. In this example, algorithm400 receives an input requirement 405 at Step 310. As discussed above,input requirement 405 prompts controller 335 to switch input/outputelement 330.

If, e.g., input requirement 365 is a power requirement 365 a, algorithm400 proceeds to Steps 415-460, which instruct controller 335 to switchinput/output element 330 into a power mode. At step 415, algorithm 400allows any input/output operation in progress at the time the powerrequirement is received to be completed. Then, at step 420, algorithm400 instructs controller 335 (FIG. 3) to disable the input/output andsignal this disablement to integrated circuit chip 305. Next, at steps425 and 430, algorithm 400 instructs controller 335 to connect switchingdevice 345 to power supply 315 and switching device 350 to power network225. Then, at steps 435 and 440, algorithm 400 instructs controller 335to acknowledge the power requirement by signaling to integrated circuitchip 305 and waiting for the completion of the necessary function, assignaled by the power requirement 365 a. Finally, at steps 445, 450,455, and 460, algorithm 400 instructs controller to connect switchingdevice 345 to signal path 310, connect switching device 350 to internalsignal path 320 and remove the power requirement acknowledgement.

Referring back to FIG. 3, an optional implementation of system 300 alsoincludes an optional receiver 375 that may be used in a receiverimplementation, discussed in more detail below. A receiver (e.g.,receiver 375) is known in the art. In addition to receiver 375, system300 may include other optional electrical components. The presentexample, for instance, includes a flush latch 380 that electricallycommunicates with receiver 375, as illustrated in FIG. 3. Examples of aflush latch include, without limitation, any memory element that can beconfigured to hold its existing state in one mode, or pass an inputstate directly to its outputs in a flush mode. This example alsoincludes optional resistors 385 a, 385 b. Examples of resistors include,without limitation, a pull-up resistor, a pull-down resistor, and anyresistor or other device that functions so as to hold a node at aspecific level. It can be appreciated that these components arerecognized in the art such that they need not be described in any detailherein.

In a receiver implementation, system 300 may operate in a signal mode ora power mode. In a signal mode, system 300 switches switching device 345to electrically connect with receiver 370. Switching device 350 isswitched to electrically connect with signal path 310. Flush latch 380is maintained in a flush state. In a power mode, system 300 switchesswitching device 345 to electrically connect with power network 325.Switching device 350 is switched to electrically connect with powersupply 315. The value at the input to receiver 375 is set to knownsignal level (e.g., a voltage level) using resistor 385 a. Flush latch380 is maintained in a retain state.

Another optional implementation of system 300 includes an optionaltransmitter 390 that may be used in a transmitter implementation,discussed more below. A transmitter (e.g., transmitter 390) is aninput/output driver, or any other IC driver circuit known in the art. Ina transmitter implementation, system 300 may operate in a signal mode ora power mode. In a signal mode, system 300 switches switching device 345to electrically connect with transmitter 390. Switching device 350 isswitched to electrically connect with signal path 310. In a power mode,system 300 switches switching device 345 to electrically connect withpower network 325. Switching device 350 is switched to electricallyconnect with power supply 315. Signal path 320 is modified to a knownsignal level (e.g., a voltage level) using resistor 385 b. Flush latch380 is maintained in a retain state.

Exemplary embodiments have been disclosed above and illustrated in theaccompanying drawings. It will be understood by those skilled in the artthat various changes, omissions and additions may be made to that whichis specifically disclosed herein without departing from the spirit andscope of the present invention.

1. A circuit for selectively connecting an integrated circuit to aplurality of external paths, the plurality of external paths including afirst signal path and an external power supply, the circuit comprising:a second signal path internal to the integrated circuit; a power networkinternal to the integrated circuit; and an input/output elementconfigured to switch amongst a plurality of modes including a first modeand a second mode, the first mode connecting the first signal path tosaid second signal path via said input/output element, the second modeconnecting said power network to the external power supply via saidinput/output element.
 2. A circuit according to claim 1, wherein saidinput/output element comprises: an input/output wire; and a firstswitching device internal to the integrated circuit for selectivelyconnecting said input/output wire to the second signal path when theinput/output element is connected to the first signal path andconnecting said input/output wire to the power network when theinput/output element is connected to the external power supply.
 3. Acircuit according to claim 2, wherein said input/output elementcomprises a second switching device for selectively connecting theinput/output wire to the first signal path when the first switchingdevice is connected to the second signal path and connecting theinput/output wire to the external power supply when the first switchingdevice is connected to the power network.
 4. A circuit according toclaim 1, further comprising a controller in communication with saidinput/output element for instructing the input/output element to switchamongst the plurality of modes.
 5. A circuit according to claim 4,wherein the controller includes an algorithm, said algorithm having aset of instructions for instructing the input/output element to switchamongst the plurality of modes.
 6. A circuit according to claim 1,further comprising a receiver in electrical communication with the firstsignal path, said receiver configured to operate as a function of theplurality of modes.
 7. A circuit according to claim 1, furthercomprising a transmitter in electrical communication with the firstsignal path, said transmitter configured to operate as a function of theplurality of modes.
 8. A circuit for selectively connecting one or moreexternal paths with an integrated circuit, the one or more externalpaths including a first signal path, the circuit comprising: a secondsignal path internal to the integrated circuit; a power network internalto the integrated circuit; a first means for switching amongst aplurality of inputs including said second signal path and said powernetwork; a second means in electrical communication with said firstmeans, said second means for switching amongst a plurality of externalpaths including the first signal path and the power supply, wherein whensaid first means is connected to said second signal path, said secondmeans is connected to the first signal path such that said second signalpath and the first signal path are in electrical communication, and whensaid first means is connected to said power network, said second meansis connected to the external power supply such that said power networkand the power supply are in electrical communication.
 9. A circuitaccording to claim 8, further comprising a first input/output pin, saidinput/output pin in electrical communication with the first signal pathand the power supply.
 10. A circuit according to claim 8, wherein saidfirst means and second means are located internal to the integratedcircuit.
 11. A circuit according to claim 8, further comprising secondinput/output pin, said second input/output pin in electricalcommunication with said second means.
 12. A circuit according to claim8, further comprising a controller in communication with said firstmeans and said second means, said controller configured to instruct saidfirst means to switch amongst the plurality of inputs including saidsecond signal path and said power network and to instruct said secondmeans to switch amongst said plurality of inputs including the firstsignal path and the external power supply.
 13. A circuit according toclaim 12, wherein said controller includes an algorithm, said algorithmhaving a set of instructions for instructing said first means and saidsecond means to switch amongst said plurality of inputs.
 14. A method ofmodifying the power supply current to an integrated circuit, theintegrated circuit having an input/output pin, the method comprising:determining a power supply requirement from the operation of theintegrated circuit; and alternately connecting the input/output pin toan external signal path or an external power supply as a function of thepower supply requirement.
 15. A method according to claim 14, furthercomprising: measuring a power operation requirement as a function of thepower consumption of the integrated circuit; and assigning the poweroperation requirement to the power supply requirement.
 16. A methodaccording to claim 14, further comprising: measuring a bandwidth signalrequirement as a function of the processing capability of the integratedcircuit; and assigning said bandwidth requirement to the power supplyrequirement.
 17. A method according to claim 14, further comprisingconnecting the external power supply to a power network internal to theintegrated circuit.
 18. A method according to claim 14, furthercomprising connecting the external signal path to a second signal pathinternal to the integrated circuit.
 19. A method according to claim 14,further comprising resetting the input/output pin so as to cause theexternal power supply current to the integrated circuit to return to aninitial level.